[lldb][docs] Add troubleshooting section to scripting introduction

Logs just helped someone on Discord debug an issue in a way that would
not have been possible just by stepping the Python script. It was that
LLDB could not find the lldb-server binary.

We do talk about logs elsewhere but I think it's fine to repeat
here since it's a lot of people's first experience with scripting.

Author: DavidSpickett

lldb/docs/use/tutorials/implementing-standalone-scripts.md

@@ -147,3 +147,20 @@ SBFunction: id = 0x0000002e, name = main, type = main
 a.out[0x714]: mov    w0, #0x0                  ; =0
 a.out[0x718]: ret
 ```
+
+### Troubleshooting
+
+You can use all the usual Python tools to debug scripts, and on top of that
+you can enable LLDB's log channels. To do this in the script shown above, add
+this line right after `debugger` has been assigned:
+
+```python
+debugger.EnableLog("lldb", ["all"])
+```
+
+`lldb` `all` enables a lot of different channels, so you will probably want
+to enable only a few channels once you know what you are interested in.
+
+This API call is the equivalent of `log enable lldb all` when using LLDB
+interactively. All channels available to `log enable` can be enabled using
+`EnableLog` too.